It has been proposed in U.S. Pat. No. 2,890,213, Canadian Pat. No. 696,260, and British Pat. Nos. 799,952 and 834,905 to chlorinate solid, finely divided polyethylene, i.e., polyethylene powder wherein the individual particles have a size below 300 microns and predominantly below 80 microns, directly in the vapor phase and without the use of solvent by suspending such powder in a stream of chlorine at temperatures below 100.degree. C. wherein chlorine, in amounts of from about 30 to 65 percent of polymer weight, is substantially heterogeneously distributed along the outer surfaces of the polyethylene particles. The use of such finely divided particles, i.e., high surface area powders, is disclosed as being necessary to achieve adequate rates and amounts of chlorination. Disadvantageously, such finely divided polymer particles produce excessive dust with accompanying atmospheric pollution and explosive hazards.
U.S. Pat. No. 3,547,866, recognizing the tendency of small particle size (high surface area) polyethylene to dust and agglomerate, discloses the utilization of polyethylene starting materials of larger particle size, i.e., particles of from 200 to 800 microns in size but which are further characterized by having a relatively low surface area, i.e., a surface area of from 70 to 300 cm.sup.2 /gram.
Further, British Pat. No. 1,228,922 uses polyethylene materials of relatively large particle size, i.e., from 400 to 5,000 microns, but like U.S. Pat. No. 3,547,866 utilizes polymer powders having a relatively low surface area, i.e., a surface area of from 20 to 100 cm.sup.2 /gm, which limits the desired rate and extent of chlorination utilizing a fluidized-bed chlorination technique.
In view of the foregoing, it would be highly desirable to provide a means for the fluid-bed chlorination of olefin polymer powder wherein the polymer powder particles are of sufficient size to prevent dusting with accompanying elimination of atmospheric pollution and explosion hazard, and wherein such polymer powder particles have a surface area of sufficient size to permit an enhanced rate of chlorination.
It is further desirable to provide chlorinated products which do not agglomerate during or after the chlorination reaction.